THERMAL-MECHANICAL BUCKLING FAILURE OF MULTILAYERED BEAM-PLATE WITH ARBITRARY DELAMINATION LOCATION

摘要

An extended one-dimensional interface crack model is proposed to analyze the thermal-mechanical buckling behavior of multilayered beam-plate with arbitrary interface crack location under clamped boundary condition. The equilibrium equations, stability equations and characteristic equation governing buckling under thermal and mechanical loads are derived based on the first order shear deformation and state space method (SSM). The extended model was used to study the thermal-mechanical buckling failure of thermal barrier ceramic coatings system (TBCs) with arbitrary delamiantion location. The TBC system consists of superalloy substrate, bond coat, thermal growth oxidation (TGO) and top ceramic coating. It was loaded by a compressive applied mechanical load along the axial direction and a high temperature gradient along the thickness direction. The critical buckling loads such as the mechanical loads and thermal loads were obtained under the combination of different conditions. Finally the influence of the beam-plate aspect ratio, the transverse shear and the temperature gradient on buckling failure difference is all discussed.